<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .play-ground {
            width: 600px;
            height: 300px;
            border: 1px solid red;
            position: relative;
        }

        .ball {
            background: aqua;
            border-radius: 50%;
            position: absolute;
            animation: ball 4s infinite;
        }

        @keyframes ball {
            0% {
                width: 50px;
                height: 50px;
                left: 30px;
                top: 130px;
            }

            25% {
                width: 25px;
                height: 25px;
                left: 130px;
                top: 20px;
            }

            50% {
                width: 100px;
                height: 100px;
                left: 240px;
                top: 100px;
            }

            75% {
                width: 80px;
                height: 80px;
                left: 420px;
                top: 70px;
            }

            100% {
                width: 150px;
                height: 150px;
                left: 420px;
                top: 70px;
            }
        }
    </style>
</head>

<body>
    <div class="play-ground">
        <div class="ball"></div>
    </div>
</body>

</html>